<!DOCTYPE html>
<html lang="zh_CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>电子邮件</title>
    <script>
        var email = prompt("请输入邮箱:");
        var emailReg = /^\w{3,}(\.\w+)*@[A-z0-9]+(\.[A-z]{2,5}){}1,2$/;
        document.write(emailReg.test(email));
    </script>
</head>
<body>
    

    
</body>
</html>